Pneumatic gaging apparatus



July 25, 1961 D. B. KIRK PNEUMATIC GAGING APPARATUS Filed May 13, 195932 l VENTOR partd fi- K179i rwcew w ATTORNEY Patented July 25, 19612,993,364 PNEUMATIC GAGING AriPARATUS David B. Kirk, Oreland, Pa,assignor to Moore Products (10., Philadelphia, Pa., a corporation ofPennsylvama Filed May 13, 1959, Ser. No. 813,023 8 Claims. (Cl. 73-375)This invention relates to pneumatic gaging apparatus and moreparticularly to pneumatic gaging apparatus for use with grinders and thelike for determining the general dimensional trend of a series of partsbetween limits, for repetitively measuring a single part as the size isgradually changed to terminate operations at a desired size, or forother purposes.

It is the principal object of the present invention to provide pneumaticgaging apparatus in which an improved pneumatic circuit is provided withthe structure for determining the time constant more compact thanheretofore.

It is a further object of the present invention to provide pneumaticgaging apparatus in which the separation of the responsive portion ofthe apparatus from the measuring portion, which is rendered necessary ingaging apparatus employed with grinders and the like, is accommodated inan improved manner.

It is a further object of the present invention to provide pneumaticgaging apparatus having separated measuring and responsive portions inwhich the responsive portion is isolated in a simple but effectivemanner.

It is a further object of the present invention to provide a pneumaticgaging component in which requisite parts of the apparatus are combinedin a compact but effective manner.

Other objects and advantageous features of the invention will beapparent from the description and claims.

The nature and characteristic features of the invention will be morereadily understood from the following description, taken in connectionwith the accompanying drawings forming part thereof, in which:

FIGURE 1 is a diagrammatic view of a gaging circuit in accordance withthe present invention;

FIG. 2 is an end elevational view showing a preferred form of thepneumatic gaging apparatus in accordance with the invention;

FIG. 3 is a side elevational view of the apparatus shown in FIG. 2;

FIG. 4 is a fragmentary vertical sectional view, enlarged, takenapproximately on the line 44 of FIG. 3;

FIG. 5 is a fragmentary horizontal sectional view taken approximately onthe line 5-5 of FIG. 4;

FIG. 6 is a horizontal sectional view taken approximately on the line 66of FIG. 4; and

FIG. 7 is a horizontal sectional view taken approximately on the line7-7 of FIG. 4.

It should, of course, be understood that the description and drawingsherein are illustrative merely, and that various modifications andchanges can be made in the structure disclosed without departing fromthe spirit of the invention.

Like numerals refer to like parts throughout the several views.

Referring now more particularly to FIG. 1 of the drawings, a pneumaticgaging circuit is there shown which includes a connection 10 to a sourceof fluid under pressure and preferably filtered air under pressure,which is connected to a pressure regulator PR.

A fluid connection 1 1 is provided from the pressure regulator PR to anupstream orifice or restriction 12 which is preferably fixed, and afluid connection 13 is provided from the restriction 12 to a nozzle 14.

The fluid connection 13 can also have a branch connection 13a extendingtherefrom to a nozzle 15, the nozzles 14 and 15 serving for externallinear opposite face, or diametrical or out of round, dimensionmeasurement.

The fluid connection 13 at a location between the restriction 12 and thenozzles 14 and 15, has a fluid connection 16 connected thereto fortransferring the pressure effective in the fluid connection 13. Thepressure in the connection 13 is determined by the dimensions of thework to be gaged, the pressure being affected between certain limits bythe positioning of the work in its relation to the terminals of thenozzles 14 and 15 and thereby controlling the discharge therefrom.

The fluid connection 16 is connected to any desired fluid pressureresponsive apparatus.

For purposes of indication, the fluid connection 16 can have a visualindicating dial type pressure gage 17 connected thereto.

For purposes of control, the fluid connection can have a controller 18connected thereto, the controller 18 having a separate pressure fluidsupply connection 19 and a regulated pressure fluid delivery connection20 to apparatus (not shown) to be controlled.

The fluid connection 16 can also be connected to a fluid pressureactuated electric switch 21, if desired.

The fluid connection 16 has an adjustable bleed 22 connected thereto fordetermining the rate of discharge of the fluid in the fluid connection16.

The fluid connection 16 between its place of connection to the fluidconnection 13 and other fluid pressure responsive equipment, such as thedial gage 17, the controller 18 or the switch 21, is provided with acheck valve 25 permitting flow towards the pressure responsiveinstruments and preventing any return flow.

Referring now moreparticularly to FIGS. 2 to 7, inclusive, in which aparticular embodiment of the invention is shown, a mounting plate isprovided having a vertical slot 31 for adjustably securing the same withstuds (not shown) at the desired position of adjustment. The mountingplate 30 has a frame 32 secured thereto in any desired manner, such asby adjusting bolts 33 extending through horizontally elongated slots 34in the mounting plate 30 with nuts 35 thereon in a horizontal groove 36at the rear of the mounting plate 30. The frame 32 has a horizontalopening 37 therethrough for the passage of the work piece and may haverails 38 therein for supporting the work piece P to be gaged.

An upper nozzle body 40 is provided, shown in more detail in FIGS. 4, 5,6 and 7. The upper nozzle body 40 is vertically adjustably mounted inthe frame 32 for relatively coarse adjustment by interiorly disposedlocking blocks 41 drawn into gripping engagement therewith by a threadedstud 42 accessible on the exterior of the frame 32 (see FIG. 5.)

The upper nozzle body 40 can be constructed in any desired manner, butas illustrated in FIG. 4 is preferably made of a plurality of partscapable of more easy manufacture and assembly in the completed form andincludes upper and lower sections 40a and 40b in threaded engagement asat 43 with each other, the upper section 40a having an extension 44 intoa bore 45 in the lower section 40b. A packing ring 46, such as an O ringis provided for preventing fluid leakage and the lower end of theextension 44 has cross slots 47 communicating with a central bore 48therein. A connector 49 is provided at the upper end for the attachmentof a fluid connection 116 such as a flexible tube which extends to theresponsive means and corresponds to the fluid connection 16 of FIG. 1.

The lower section 40b of the upper nozzle body 40 is provided with acentral bore 50 aligned with the bore 49 and having an enlargement 51 atits lower end for the insertion of a nozzle 114 terminated inwardly withrespect tothelower end of the body 40- to prevent wear thereof. Radiallyextending air exhausting. openings 52 may also be provided for the freedischarge of air delivered through the nozzle 114. The body section 40bis provided with a bore 53 in intersecting relation to the bore 50 witha fluid connection 111 having a fixed restriction 112 therein, thisrestriction corresponding to the restriction 12 illustrated in FIG. 1,and being connected to a source of pressurefluid, such as air atregulated pressure available from the pressure regulator PR.

The bore 50 also has in communication therewith an inserted connector 55with a fluid connection 113a, flexible in type, extending to the lowernozzle 115, as hereinafter explained.

The upper nozzle body 40 opposite the location of the insert in whichthe restriction 112 is provided, can have a screw plug 56 removable foraccess to the restriction 112 for cleaningthe same.

The lower end of the bore 45 of the upper nozzle body 46 has a packingmember 57, such as an O ring, therein, the extension 44 is terminated inspaced relation to the packing ring 57 and a valve disc 58 of lightweight non-corrosive material, smaller in diameter than the bore 45, andpreferably of synthetic plastic resistant to corrosion, such as mylar,teflon, nylon or the like, is provided. The disc 58, with the packingring 57 provides a check valve opening upward, corresponding to thecheck valve 25, and closing by gravity and pressure thereon from abovefor preventing downward-or return flow.

A lower nozzle body 60 is also provided preferably having a head 61 atthe lower end and a threaded portion 62 for fine adjustment extendingthereabove and in threaded engagement in the frame 32. A look nut 63 iscarried thereon for locking the same in adjusted position.

The frame 32. has a fluid connection 64 extending thereinto and to whichthe flexible tube 113a extends, with a port 65 intersecting a bore 66 inthe frame 32.

The upper end of the lower nozzle body 60 extends upwardly within thebore 66, and has an annular recess 67 for positioning in communicationwith the port 65 for establishing communication therewith. The nozzlebody 60 also has an interior passageway 59 with an enlargement at theupper end into which the nozzle 115 is inserted. The nozzle 115 isterminated inwardly from the end of the nozzle body 60 to avoid wearthereof.

The nozzle body 60 above and below the groove 67 preferably has packingrings 68 and 69 such as rings, carried thereby for preventing fluidleakage.

The mode of operation will now be pointed out.

Air under regulated pressure is supplied through the fluid supplyconnection 11 or 111 and through the restriction 12 or 112 forsimultaneous discharge through the upper nozzle 14 or 114 and throughthe fluid connection 13a or 113a to and through the lower nozzle 15.

or 115. The orifices, determined by the position of the work piece Pwith respect to the terminal ends of the upper nozzle 14- or 114 and thelower nozzle or 1 15, will determine the pressure prevailing in thefluid connection 16 or 116 between the restriction 12 or 112 and thenozzles 14 or 114 and 15 or 115. This pressure is effective through thecheck valve 25 or disc 58 and ring 57 and at the measuring elements suchas the dial gage 17, controller 18 and/ or switch 211. The bleed 22 willpermit the pressure in the fluid connection 16 or 116 to fall untilrestored by a subsequent gaging operation with interposition of a workpiece between the nozzles14 or.114 and 15 or 1.15.

As successive work pieces pass between the gaging nozzles 14 and 15, thepressure rises in line 13 corresponding to the maximum dimension of eachpiece. To reach the ultimate pressure possible, in a short time,requires that the volume of line 13 be kept small. As the pressure risesin line 13, it will eventually exceed the pressure in line 16, and thecheck valve 25 will open. Because of the added volume of line 16, thesubsequent rise of pressure in line 13 will be slower but after severalpieces have passed through the gage, the pressure in line 16 will havebeen increased nearly to the peak pressure in line 13. The bleed valve22 provides for a slow reduction of the pressure in line 16 but does notbleed off enough fluid to cause a substantial drop in line 16 betweensuccessive peaks of pressure in line 13. By making the bleed smaller atthe bleed valve 22, the average pressure in line 16 can be made toapproach the peak pressure in line 13 as closely as desired. In thiscondition, line 13 is isolated from line 16 except for an instant whenit has approached its peak pressure as closely as desired, and its timeconstant will be determined almost entirely by the volume of line 13 andwill not be influenced by the much larger volume of line 16 and theassociated equipment.

With optimum adjustments as described above, the gage will measure thetrend of part size rather than individual part sizes. A badly undersizepart will result in a low peak pressure in line 13, out the rate ofbleed from valve 22 is such that the pressure in line 16 would not dropoil an appreciable amount before a succeeding normal part again raisedthe peak pressure to the normal range and restored the pressure in line16. Similarly, a single successive oversize part passing through thegage would cause the pressure in line 13 to rise to the normal peakvalue at the high rate determined by the time constant of, line 13. Thepressure would continue to rise beyond this point at the much lower ratedetermined by the time constant of combined lines :13 and 16, and thetotal rise for one oversize part would be small. The succeedingnormal'part would produce the normal peak pressure in line 13 and anyslight excess in line 16 caused by the previous part would bleed offthrough valve 22.

If the trend of part size should increase, however, then all of theparts coming through the gage would be large, and the peak pressure oneach successive part would be higher causing a gradual increase in thepressure in line 16 until it equaled the peak pressure in line 13corresponding to the changed size.

Departures from a predetermined lower limit, or upper and lower limits,of dimensions of the work piecel will be visibly indicated at theinstrument 17, and can be employed at the instruments 18 or 21 for acontrol function, so that if other than an occasional departure frompredetermined dimensions occurs with a work piece P, the trend will benoticeable and utilized by the control instrument 18 or 21 for anydesired purpose, such for example as changing the positioning of acutting element (not shown) to overcome the trend and restore conditionsto the desired operating level, or for changing the positioning of acutting element (not shown) in a step by step change.

I claim:

1. In measuring apparatus, a source of fluid under regulated pressure, agage member having a discharge opening controlled by the dimension ofthe work to be measured, a first fluid connection between said sourceand said gage member having a restriction therein, a

r second fluid connection connected to said first fluid connectionbetween said gage member and said restriction, a fluid pressureresponsive means to which said second fluid connection is connected, anda non-return valve interposed in said second fluid connection in advanceof said responsive means, said non-return valve having inlet and outletconnections for the passage of fluid therethrough, and seating meansresponsive to the differential pressure betweensaid inlet and outletconnections.

2. Measuringapparatusas defined in. claiml: inwhich said second fluidconnection has a bleed device connected thereto in communication withthe said non-return valve and said fluid pressure responsive means.

3. In measuring apparatus, a body having an interior bore and having anend portion, a connection communicating with said bore and extendingfrom said body and connected to a source of pressure regulated fluid,said connection having a restriction therein, a gaging memher at saidend portion of said body in communication with said bore and having adischarge opening controlled by a dimension of the work to be measured,said bore having a non-return valve therein, said non-return valvehaving inlet and outlet connections for the passage of fluidtherethrough, and seating means responsive to the differential pressurebetween said inlet and outlet connections said body having a fluidconnection for the delivery of pressure fluid passing said valve.

4. In measuring apparatus, a body having an interior bore and having anend portion, a connection communicating with said bore and extendingfrom said body and connected to a source of pressure regulated fluid,said connection having a restriction therein, a gaging member at saidend portion of said body in communication with said bore and having adischarge opening controlled by a dimension of the work to be measured,said bore having an enlarged portion with a packing member therein, anda disc in said bore engageable with said packing member to provide anon-return valve in said body, said body having a fluid connection forthe delivery of pressure fluid passing said valve.

5. In measuring apparatus, an elongate body having two longitudinallyaligned portions with an interior bore and having an end portion, aconnection communicating with said bore and extending from said body andconnected to a source of pressure regulated fluid, said connectionhaving a restriction therein, a gaging member at said end portion ofsaid body in communication with said bore and having a discharge openingcontrolled by a dimension of the work to be measured, said body betweeninterior parts of said aligned portions having a chamber with which saidbore is in communication, said chamber having a packing member therein,a disc in said chamber engageable with said packing member to provide anonreturn valve in said body, said body having a fluid connection forthe delivery of pressure fluid passing said valve.

6. Measuring apparatus comprising a frame having an openingtherethrough, a first gaging member carried by said frame inintersecting relation to said opening, said first gaging member having afirst nozzle, a second gaging member in intersecting relation to saidopening, said sec- 0nd gaging member having a second nozzle, said firstand second nozzles having discharge openings facing towards each otherand controlled by a dimension of the work to be measured interposedtherebetween, said first gaging member having a connection to a sourceof pressure regulated fluid in communication with an interior boretherein through a restriction, said interior bore being in communicationwith said first nozzle, a fluid connection from said first gaging memberto said second gaging member, said first gaging member having anon-return valve therein and a fluid delivery connection for thedelivery of fluid passing said valve, said non-return valve having inletand outlet connections for the passage of fluid therethrough and seatingmeans responsive to the difierential pressure between said inlet andoutlet connections.

7. In measuring apparatus, a source of fluid under regulated pressure, agage member having a discharge opening controlled by the dimension ofthe work to be measured, a first fluid connection between said sourceand said gage member having a flow controlling device therein, a secondfluid connection connected to said first fluid connection between saidgage member and said device, fluid pressure responsive means to whichsaid second fluid connection is connected, and a non-return valveinterposed in said second fluid connection in advance of said responsivemeans, said non-return valve having inlet and outlet connections for thepassage of fluid therethrough, and seating means responsive to thedifferential pressure between said inlet and outlet connections.

8. In measuring apparatus, a body having an interior bore and having anend portion, a connection communicating with said bore and extendingfrom said body and connected to a source of pressure regulated fluid,said connection having a restriction therein, a gaging member at saidend portion of said body in communication with said bore and having adischarge opening controlled by a dimension of the work to be measured,a non-return valve with which said bore is in communication, saidnonreturn valve having inlet and outlet connections for the passage offluid therethrough and seating means responsive to the differentialpressure between said inlet and outlet connections, and a fluidconnection for the delivery of pressure fluid passing said valve.

References Cited in the file of this patent UNITED STATES PATENTS1,285,220 Kerstein Nov. 19, 1918 2,448,653 Aller Sept. 7, 1948 2,845,791Loxham et a1 Aug. 5, 1958

